DFT simulation to study the mechanical, electronic, thermal and superconducting properties of borocarbides materials AX2B2C where A = Y, La, Th and X = Pd, Pt

The invention of superconductivity in quaternary borocarbides has been attracted great attraction in the recent time. Here, the elastic, electronic, thermal, superconducting and optical features of borocarbides materials AX₂B₂C (A = Y, La, Th and X = Pd, Pt) have been explored through ab-initio method with the help of CASTEP code. To explore the physical features of AX₂B₂C (A = Y, La, Th and X = Pd, Pt) we used the well-known density functional simulation (DFT) in addition to generalized gradient approximations (GGA). The examined structural features displayed well covenant to the experimental data. The dynamical stability of the materials AX₂B₂C (A = Y, La and X = Pd, Pt) was ensured by the positive phonon dispersion curves where the heavier atoms (Y, La, Pd and Pt) contribute most to create the acoustic modes and lighter B and C atoms contribute most to create the optical modes. The investigated elastic constants (C_ij) hold Born's constancy standards and confirmed the mechanical constancy of the titled materials. The large Young's, bulk, and shear moduli of Pt-based superconductors AX₂B₂C (A = Y, La, Th and X = Pt) than Pd- based borocarbides ensure their high resistance to volume, length and shear deformation. The studied borocarbides phases show ductile nature in order to their Pugh's and Poisson's ratio values (B/G > 1.75 and υ > 0.26). The high machinable index confirm the damage-tolerant, high lubricant and lower friction values which ensures the industrial applications of the titled phases. The moderate Debye temperature ensure the thermal conductive nature of these compounds. The extremely elevated melting temperature and very low minimum thermal conductivity (K_min) confirm the TBC like behavior of these materials whereas the compounds LaPt₂B₂C and ThPt₂B₂C contributes the most. The calculated transition temperatures, T_c of AX₂B₂C (A = Y, La, Th and X = Pd, Pt) show well accord with the experimental transition temperatures (T_C). Finally, extraordinary reflectivity in the infrared energy site also ensure the TBC nature of these superconductors.